This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In hydroxyl radical footprinting experiments, one of the major bottlenecks is in the data analysis. Due to the broad reactivity of hydroxyl radicals and the wide variety of oxidation products, it is very difficult to automate search algorithms for identification of sites of oxidation. Currently, manual validation and correction is necessary for all preliminary oxidation site assignments. A search algorithm named ByOnic was developed to allow for automated identification of a wide variety of post-translational modifications. This algorithm has been applied to hydroxyl radical footprinting with promising preliminary results. In collaboration with the developer of ByOnic, we will work to improve ByOnic for automated identification of sites of oxidation.